Using principal component analysis to increase accuracy of prediction of metabolic syndrome in artificial neural network and logistic regression models

زمینه و هدف: در فرآیند مدل‌سازی، زمانی‌که بین متغیرهای کمکی همبستگی‌های نسبتا قوی وجود داشته باشد، هم‌خطی‌چندگانه ایجاد شده و باعث کاهش کارآیی مدل می‌گردد. هدف از این مطالعه استفاده از تحلیل مولفه‌های اصلی برای تعدیل اثر هم‌خطی‌چندگانه در مدل‌های رگرسیون لجستیک و شبکه عصبی مصنوعی و بررسی تاثیر آن بر صحت و دقت پیش‌بینی سندرم متابولیک بود. روش بررسی: در این مطالعه توصیفی – تحلیلی تعداد 347 نفر از افراد شرکت کننده در مطالعه آینده نگر قند و لیپید تهران که در فاز اول مطالعه بر اساس تعریف پانل درمان بالغین (ATPIII) مبتلا به سندرم متابولیک نبودند انتخاب شدند. ابتدا مدل‌های رگرسیون لجستیک و شبکه عصبی مصنوعی با استفاده از متغیرهای کمکی اولیه و سپس با استفاده از مولفه‌های اصلی به داده‌ها برازش گردید و پیش‌بینی بر اساس این مدل‌ها انجام شد. از تحلیل راک و آماره کاپا برای مقایسه قدرت پیش‌بینی مدل‌ها استفاده گردید. یافته‌ها: برای مدل‌های رگرسیون لجستیک، رگرسیون لجستیک با مولفه‌های اصلی، شبکه عصبی مصنوعی و شبکه عصبی مصنوعی با مولفه‌های اصلی به‌ترتیب مساحت زیر منحنی راک 749/0، 790/0، 890/0 و 927/0 به‌دست آمد، میزان حساسیت مدل‌ها 483/0، 435/0، 836/0 و 919/0، ویژگی آن‌ها 857/0، 919/0، 892/0 و 964/0 و اندازه آماره کاپا برای مدل‌ها 322/0، 386/0، 712/0 و 886/0 به‌دست آمد. نتیجه‌گیری: تحقیق نشان داد که صحت پیش‌بینی مدل‌های بر اساس مولفه‌های اصلی از مدل‌های مبتنی بر متغیرهای کمکی اولیه بیشتر بوده و بنابراین در هنگام وجود هم‌خطی‌چندگانه، مدل‌های مبتنی بر مولفه‌های اصلی برای پیش‌بینی سندرم متابولیک کاراتر هستند

The quality of family planning services in health care centers of Shahid Beheshti University of Medical Sciences: comparison of clients, providers and program managers viewpoints

Background and aim: Family planning services are frequently used and important services for women of reproductive age. These services are crucial in enabling women to meet their fertility goals. The aim of this study was to determine and compare of the quality of family planning services in urban health centers from the viewpoint of clients, employees, experts and staff managers at different levels.Materials and methods: In a cross-sectional study, 500 women who seeking care from health care center under the supervision of the Shahid Beheshti University of Medical Sciences regarding family planning services, 147 health providers, and 18 family health managers at different levels of district, provincial and national were investigated using revised SERVQUAL questionnaire.Results: The results revealed negative gap in all dimensions of service quality. There was an overall negativegap score of -0.37 between clients expectations and perceptions of service quality (p<0.001). For the health care providers, experts and staff managers, this gap was equal to -0.50 (p<0.001). On the other words the heath care providers and program managers estimated the clients expectation more than actually were and ability of health system to address to these expectations less than clients perceptions of quality.Conclusion: Negative gap between clients expected and perceived service quality should be considered seriously for planning and implementation of proper interventions for service quality improvement.Key words: Service Quality, Family Planning, Health Care Center, SERVQUA

Tuberculosis-related awareness among people living in rural areas of

    Tuberculosis is an infectious disease that caused by Mycobacterium Tuberculosis (TB). Despite the implementation of free treatment, detection rate of TB remains low. Lake of awareness is a main reason for not expressing symptoms in patients. The study aimed to determine the level ofawareness about TB among rural areas of Gorgan. This study was cross-sectional research which was conducted in 2014-2015 in Gorgan villagers (age 12≥15, '> non-TB). These individuals were selected by two-staged cluster sampling. The total sample size was 672. The data collection instrument was a researcher-made questionnaire. Face& content validity and also test-retest method were used for validity and reliability, respectively. Participation of individuals in this study was voluntary and with informed consent. The collected data was analyzed using SPSS 16 software. Findings analysis by independent Sample T-Test and Anova test. The mean age of respondents was 12 33±1.17'> . The mean score of villagers' awareness was 1230.95±6.16'> . The awareness level of 330 participants (49.1%) was high. There was a significant difference between awareness and some variables such as literacy level and age (p<0.05). There wasn't a significant difference between awareness and gender, family size, history of morbidity, and ethnicity. According to results of this study, Level of villagers'awareness about TB was high, but they lacked awareness on some aspects like the ways of transmission and virulence of disease. It seems that increasing awareness and surveying of influent factors on awareness in people who have TB symptoms is necessary.

Study of age at first myocardial infarction in patients in Iran: A national study

Background and Objectives: Determining and monitoring the age at myocardial infarction (MI) and its comparison in various regions is one of the vital and basic principles for the management of MI. This study was conducted to determine the age at the first MI in Iran. Methods: In this cross-sectional, analytical study at a national level, the data of 20750 new MI patients registered in 2012 in 31 provinces of Iran according to the cardiologist’s diagnosis, World Health Organization criteria, and the codes ICD10: 121-122 were used. The calculations were done using the Stata 12 software. Results: The mean±SD of age at the first MI was 61.2±13.4 years in all patients in Iran. Moreover, 15033 (72.4%) patients were male with a mean age of 59.6±13.3 years. The mean age at MI in men was lower than women (65.4±12.6 years), showing a statistical significance (P<0.001).The mean age at MI was different among Iran provinces, with a statistical significance (P<0.001). The lowest mean age at the first MI was seen in the patients living in Semnan (59.1±12.9 years), followed by Tehran (60.4±13.5 years), Sistan va Balouchestan (60.3±13.9 years), and Lorestan (60.1±14.5 years), with a significant difference from the mean age of the patients in Ardabil (63.2±15.1 years) and Zanjan (64.4±112.8 years) (P<0.019). Conclusion: Our study demonstrated that the age at MI was approximately five years younger in men than women. This studyprovided the ground for monitoring the age at MI, and more effective management of cardiovascular diseases in Iran

Comparison of artificial neural network, logistic regression and discriminant analysis methods in prediction of metabolic syndrome.

Introduction: Artificial neural networks as a modern modeling method have received considerable attention in recent years. The models are used in prediction and classification in situations where classic statistical models have restricted application when some, or all of their assumptions are met. This study is aimed to compare the ability of neural network models to discriminant analysis and logistic regression models in predicting the metabolic syndrome. Materials & Methods: A total of 347 participants from the cohort of the Tehran Lipid and Glucose Study (TLGS) were studied. The subjects were free of metabolic syndrome at baseling according to the ATPIII criteria. Demographic characteristics, history of coronary artery disease, body mass index, waist, LDL, HDL, total cholesterol, triglycerides, fasting and 2 hours blood sugar, smoking, systolic and diastolic blood pressure were measured at baseline. Incidence of metabolic syndrome after about 3 years of follow up was considered a dependent variable. Logistic regression, discriminant analysis and neural network models were fitted to the data. The ability of the models in predicting metabolic syndrome was compared using ROC analysis and the Kappa statistic, for which, MATLAB software was used. Results: The areas under receiver operating characteristic (ROC) curve for logistic regression, discriminant analysis and artificial neural network models (15: 8: 1) and (15: 10: 10) were estimated as 0. 749, 0. 739, 0. 748 and 0. 890 respectively. Sensitivity of models were calculated as 0. 483, 0. 677, 0. 453 and 0. 863 and their specificity as 0. 857, 0. 660, 0. 910 and 0. 844 respectively. The Kappa statistics for these models were 0. 322, 0. 363, 0. 372 and 0. 712 respectively. Conclusion: Results of this study indicate that artificial neural network models perform better than classic statistical models in predicting the metabolic syndrome

Determinants of Households Health Expenditure : A Population-Based Study

Studies have shown that the determinants of households’ health expenses are in doubt in Iran. Patients deal with pain and trouble while facing with increasing health services payments. Thus, their quality of life decreases in all aspects. The objective of this research lies on the analysis of Iranian households’ health expenditure (HHE) using multilevel modelling methodology. Data collected through Household Income and Expenditure Survey by Statistical Center of Iran. A total of 38299 Iranian households were sampled. This nationally-representative cross-sectional survey collected information from March 2013 to March 2014 using a three-staged cluster sampling method. Descriptive statistics and multilevel modelling employed for data analysis. Data analysis was performed using R programming language version 3.3.2 and SPSS version 20. P &lt; 0.05 was considered as statistically significant. Our findings indicated that families spent about seven percent of their annual income on HHE. Annual median of medical expenses and income per capita were 1020 and 44460 thousand rials, respectively. Family income, age, and activity status of household head had significant positive effects on annual HHE (P&lt;0.05). Female headed families spent about 10% less health expenses than male headed households annually (P&lt;0.001). Although, rural and illiterate heads experienced lower health expenses, their effects were not statistically substantial (P&gt;0.05). More attention on HHE will be needed from researchers and politicians, as it has proved to be no easy matter in the low-income and deprived areas

Geographical pattern of in-hospital mortality due to myocardial infarction in Iran

Background and purpose: So far, no spatial analysis of in-hospital mortality due to myocardial infarction (MI) has been conducted in Iran. The present study was performed to determine the geographical pattern of mortality due to myocardial infarction in Iran. Materials and methods: In a prospective hospital-based study, we used the data of cases with MI registered by Myocardial Infarction Registry of Iran, 2012. For spatial analysis, LISA, Global Moran’s I, and Getis-Ord’s statistics were used. Data was analyzed using Stata software and ArcGIS 9.3 Results: A total of 20,750 patients was admitted to hospital due to MI and 2511 (12.1%) deaths occurred (median age at death: 65.2 ± 15.2). The incidence of death from MI did not follow a particular pattern (Moran's Index: 0.141, P-value = 0.126). The highest standardized incidence rates of in-hospital mortality from MI in 100,000 population were observed in Ardebil (31), North Khorasan (23.7), Yazd (20.2), West Azerbaijan (19.1) and Khuzestan (18.4). The lowest incidence rates were found in Sistan-Baluchestan and Khorasan provinces. Conclusion: This study supports the hypothesis of random pattern of mortality due to myocardial infarction in Iran

Epidemiological pattern of myocardial infarction and modelling risk factors relevant to in-hospital mortality: the first results from the Iranian Myocardial Infarction Registry

Background: Myocardial infarction (MI) care and treatment contribute greatly to the patients' fatality and mortality. Assessing and monitoring mortalities and the effective factors are necessary in MI care and treatment programs. No comprehensive and population-based study has yet been conducted in Iran to determine the epidemiological pattern of MI, and particularly in-hospital mortality rate and the effective factors. Aim: To determine the epidemiological pattern of MI based on person-, time-, place-, and mortality-associated risk factors. Methods: This was a prospective, population-based cohort study, which analysed the data of 20,750 MI patients in Iran in 2012. MI was diagnosed based on ICD-10: codes I21 and I22. The cohort of the patients was defined in terms of the date at diagnosis, hospitalisation, and the date at discharge (recovery or death due to MI). The in-hospital mortality rate was calculated by Cox regression. Univariate analysis and multiple logistic regression were used to determine the effective factors on the patients' mortality. The odds ratio (95% confidence interval CI]) was reported using Stata software. Results: The relative frequency of in-hospital mortality was 12.1%. The in-hospital mortality rate was higher in women than in men, and 6.74 (95% CI 6.4-7.0) per 100 person-years were at risk of death. The highest relative mortality (13.2%) was obtained in January (11 Dey to 11 Bahman in the Persian calendar) and the lowest (5.9%) in May (11 Ordibehest to 10 Khordad in the Persian calendar). Age of over 84 years, female gender, educational level, smoking, lack of thrombolytic therapy, type 2 diabetes, chest pain prior to arriving in hospital, right bundle branch block, ventricular tachycardia, percutaneous coronary intervention, lateral MIs, and ST segment elevation myocardial infarction (STEMI) were determinants of in-hospital mortality in the patients. The relative frequency of mortality was higher from STEMI (83.7% of deaths in registry) vs. non-STEMI (16.3% of deaths in registry). Conclusions: STEMI, lack of thrombolytic therapy, age of over 84 years, and ventricular tachycardia have the greatest effect on in-hospital mortality in MI patients. The results of this study are helpful in planning for monitoring and promotion of healthcare of the patients

Availability and Accessibility of Fruit and Vegetable in Home and School for Iranian Students: A Cross-sectional Research in Schools of Tehran, Iran

Background: Availability and accessibilityarereported as the main determinants of fruit and vegetable consumption among children. The present study was conducted to assess the status of availability and accessibilityto fruit and vegetable at school and home among Iranian adolescents in Tehran, Iran. Materials and Methods: This cross-sectional study was conducted to assess status of fruit and vegetable availability and accessibilityamong Iranian adolescents. In this study, 500 adolescents aged 11 to 14 years old were investigated in Tehran, Iran. Subjects were chosen by multi-stage random sampling method. The data collection tool was a valid researcher-made questionnaire consist of 21 questions. The data was analyzed using SPSS software version 16.0. Results 68% (n=344) and 27.2% (n=136) of students reported that fruit and vegetables is available in their home always, respectively. Also, 19.6% (n=98), and 58.4% (n=292) of students reported that most of the times and always unhealthy foods were sold in schools’ buffets, respectively; 88% (n=440) of students declared that they are allowed to take fruit and vegetable from the refrigerator and eat any time they want to. Results showed no significant difference between boys and girls in terms of availability and accessibility(P=0.268). In addition, there was a significant relationship between variables of residential area, family and home size, birth order and the parents’ education level and availability and accessibility (

Difference in clinical manifestations of myocardial infarction between men and women in Iran in 2014-2015

Background and aims: Cardiovascular diseases are the main cause of mortality among men and women so that the difference in acute myocardial infarction (AMI) symptoms between men and women can affect diagnosis and time of decision making for treatment and consequently disease outcomes. Therefore, knowledge of different symptoms affects the prognosis of the disease according to the gender. This study was conducted to determine the difference in clinical manifestations of MI between men and women. Methods: In this cross-sectional, descriptive-analytical study all patients with primary diagnosis of AMI (n: 33831) in Iran in 2014-2015 were included. Data analysis was done by Stata. For descriptive data, central indices and distribution were used, and for investigation of the association among the variables, independent t-test and logistic regression were used. Results: Overall, 33831 patients were included in this study, of whom, 24532 (51.72%) were male and the rest were female. Mean age at MI incidence was 80.0 7.59 years in men and 13.66 13.0 in women. Being female increased the likelihood of dyspnea by 3.1 times, vomiting by 31.1 times, and jaw pain by 21.1 times. No significant difference was seen in left arm pain, chest pain, nausea, and sweating between men and women (P>0.05). Conclusion: Atypical symptoms, particularly in women, may cause the delay in referring the patients and also delay in decision making for diagnosis and treatment by the medical team. Hence, staff and patients of ICUs need more special information about AMI symptoms, especially with regard to gender